Frequently Asked Questions
OSHA 1910.184 states that alloy chain slings are required to be visually inspected daily by a competent person designated by the employer. The severity of conditions may require frequent inspection throughout the day. The daily chain sling inspections are not required to be documented by OSHA.
OSHA also requires that, once within any 12 month period, all alloy chain slings are required to be thoroughly visually inspected and the condition of each sling be documented by a competent person. The employer also must maintain a record of the latest chain sling inspection and make that inspection report available for examination.
The chain sling manufacturer must complete an Alloy Chain Sling Certificate for each chain sling assembled and tagged according to OSHA. The sling certificate is required to be maintained for each chain sling and made available for examination.
Along with the Alloy Chain Sling Certificate, the employer must maintain a record of the most recent periodic Chain Sling Inspection Report and the report be made available for examination.
The hooks on multi-leg chain slings should always be facing in the outward direction away from the center of the load. This will allow the hooks to seat properly into the bowl of the hook at the connection point. It also permits the retainer latch to perform its function in a slack condition.
No. If the load has more than two connection points and they are being attached to the hoist or crane at a single point, then you must rate the lifting capacity as a 3 & 4-leg chain sling. The information is available in the Alloy Chain Sling Capacity Chart available in the Peerless Chain catalog, Chain Sling User’s Manual, and Wall Capacity Charts.
The distance is not as important as the angle of lift in relation to load. The angle the chain forms between the connection point and the crane hook cannot be less than 30 degrees. When the angle of lift is at 30 degrees, each chain leg will see the same weight as the load being lifted.
The answer depends on the Grade of alloy you are using. Grade 63, 80, and 100 have different heat effect charts. Grade 100 is the most susceptible to higher temperatures but both 80 and 100 begin to show reduced capacities at 400 degrees F. Grade 63 is the least effected by heat. Grade 63 has no permanent high heat effects until it reaches 850 degrees.
Grade 100 has about a 25% greater working load limit when compared to Grade 80. Both grades are characteristically identical when used on alloy chain slings to lift heavy loads. The higher WLL that Grade 100 offers makes it a more ergonomically efficient sling to use when the load weight fall between the two grades’ capacities.
The following items are the most common defects discovered when completing a chain inspection:
- Missing ID Tag, Incorrect information or illegible ID Tag
- Sling chain not alloy – Homemade chain or attachments
- Altered or modified attachments
- Elongated (stretched) links or sling legs
- Bent or twisted Links
- Drag wear
- Nicked or gouged links
- Severe corrosion or pitting
- Worn links or hooks
- Open or bent hook
- Weld Splatter
- Mechanical coupling link not hinging properly
- High heat damage “bluing”
Should, when reading any government document, means that the criteria as stated is a recommendation. The criteria still has to be followed; however, there can be valid reasons for taking exception to it.
Shall or Must means that the criteria as stated has to be followed verbatim. There are no exceptions to the requirement as stated. Violations of non-compliance with these criteria often result in fines following an audit or incident investigation.
The answer is simple. Any elongation which occurs in alloy chain is criteria for removal. Alloy chain has a minimum elongation of 20% before failure so any lengthening of the links or legs is criteria for removal.
ASTM A906/A906M-2 states that when a new chain sling is manufactured, there is an allowable difference in length between the hooks on multiple leg chain slings. The maximum difference in length is 5/16” for slings up to 6-1/2 ft. in length. Then, for every additional 3-1/4 ft., the difference can increase by an additional 5/32”. Technological advances in chain manufacturing has greatly improved the consistency of chain length so this standard is not as much of a concern as it once was.
Some of our old timers that work in the shop lock their chain slings up in their tool boxes when the inspectors come through to do the annual inspection. They are afraid of losing them if the inspectors find a problem and have to tag them out for repair. Which chain slings in our facility are required to be inspected?
OSHA 1910.184 states that ALL alloy chain slings are required to have a documented inspection once within a 12 month period. If the inspectors detect removal criteria on a chain sling, the location is documented and the new or repaired chain sling will be designated to be returned their area. A defective chain slings could present the possibility of a catastrophic failure occurring that could result in injury or death.
Nicks occur as a result of the alloy chain coming into contact with a sharp metal edge or corner. The metal begins to penetrate the chain as the lift is being made and the chain is seeing the entire load weight. A few nicks are acceptable for the chain to remain in service; however, if they become numerous, are located near or on the crown or radius area of any given link, or penetrate 10% of the links’ material diameter, then the sling must be removed and evaluated for repairs.
Nicks can be averted with the use of wear pads between the chain and sharp corners.
Gouges commonly occur when the load is in a basket or choke hitch. As the sling begins to see an increase in load weight and adjusts itself toward the center of gravity, the force that is applied between the chain link and metal also increases. When this happens simultaneously, the tension and adjustment make the sharp corner in-bed itself into the chain link. This is what forms a deep gouge. If the gouge removes 10% or more of a given links’ material diameter or if the gouge occurs at or near the crown or radius area, remove the chain from service. If the gouged area is in question, contact a qualified chain expert to assess the sling further.
Gouges can be limited or prevented with the use of wear pads placed between the alloy chain and the sharp edges.
My guys were lifting a large uneven box on the job site with a four-leg chain sling and they twisted the chain in order to shorten two of the legs. After the load was set and released, the chain on those two legs appears to have a slight twist in them from top to bottom. Do I need to tag the sling out of service?
YES! Alloy chain is designed to lift in a straight link-to-link pull. All the welds need to line up in the same plane from top to bottom for the chain to function properly. If the chain is bent or twisted, it must be removed from service and sent to a qualified service center for repair.
The use grab hooks as adjusters should be used to shorten the legs of alloy chain slings.
A. Single individual master links can only accommodate single and double leg alloy chain slings. All 3 and 4 leg alloy chain slings are required to be assembled onto a master-sub assembly per ASME B30.9. The assembly must had been proof tested to 6 times the working load limit of a single leg sing for the specified diameter of chain.
B. Peerless mechanical coupling links are designed to accommodate only 1 component per link. That will be either the top link of chain on the leg or the eye of a grab hook being used as an adjuster leg. The mechanical coupling link will not function properly is there are 2 legs of chain or chain and a grab hook on the same link.
When selecting a master link for a conventional standard crane hook, the master link should be at least 1” wider than the width of the crane hook. This will allow the inside radius of the master link to maintain a bearing-to-bearing connection with the bottom of the crane hook bowl. If not, the master link is too small and needs to be replaced. If there is not a bearing-to-bearing connection and the master link is pressing onto the edges, this will create a stress point at which the master link can fail or the crane hook will wear out prematurely in that area. This is a costly replacement that can be averted with the correct sized master link.